quantum/variable_trace.c

   1 /* Copyright 2016 Fred Sundvik
   2  *
   3  * This program is free software: you can redistribute it and/or modify
   4  * it under the terms of the GNU General Public License as published by
   5  * the Free Software Foundation, either version 2 of the License, or
   6  * (at your option) any later version.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License
  14  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  15  */
  16
  17 #include "variable_trace.h"
  18 #include <stddef.h>
  19 #include <string.h>
  20
  21 #ifdef NO_PRINT
  22 #    error "You need undef NO_PRINT to use the variable trace feature"
  23 #endif
  24
  25 #ifndef CONSOLE_ENABLE
  26 #    error "The console needs to be enabled in the makefile to use the variable trace feature"
  27 #endif
  28
  29 #define NUM_TRACED_VARIABLES 1
  30 #ifndef MAX_VARIABLE_TRACE_SIZE
  31 #    define MAX_VARIABLE_TRACE_SIZE 4
  32 #endif
  33
  34 typedef struct {
  35     const char* name;
  36     void*       addr;
  37     unsigned    size;
  38     const char* func;
  39     int         line;
  40     uint8_t     last_value[MAX_VARIABLE_TRACE_SIZE];
  41
  42 } traced_variable_t;
  43
  44 static traced_variable_t traced_variables[NUM_TRACED_VARIABLES];
  45
  46 void add_traced_variable(const char* name, void* addr, unsigned size, const char* func, int line) {
  47     verify_traced_variables(func, line);
  48     if (size > MAX_VARIABLE_TRACE_SIZE) {
  49 #if defined(__AVR__)
  50         xprintf("Traced variable \"%S\" exceeds the maximum size %d\n", name, size);
  51 #else
  52         xprintf("Traced variable \"%s\" exceeds the maximum size %d\n", name, size);
  53 #endif
  54         size = MAX_VARIABLE_TRACE_SIZE;
  55     }
  56     int index = -1;
  57     for (int i = 0; i < NUM_TRACED_VARIABLES; i++) {
  58         if (index == -1 && traced_variables[i].addr == NULL) {
  59             index = i;
  60         } else if (strcmp_P(name, traced_variables[i].name) == 0) {
  61             index = i;
  62             break;
  63         }
  64     }
  65
  66     if (index == -1) {
  67         xprintf("You can only trace %d variables at the same time\n", NUM_TRACED_VARIABLES);
  68         return;
  69     }
  70
  71     traced_variable_t* t = &traced_variables[index];
  72     t->name              = name;
  73     t->addr              = addr;
  74     t->size              = size;
  75     t->func              = func;
  76     t->line              = line;
  77     memcpy(&t->last_value[0], addr, size);
  78 }
  79
  80 void remove_traced_variable(const char* name, const char* func, int line) {
  81     verify_traced_variables(func, line);
  82     for (int i = 0; i < NUM_TRACED_VARIABLES; i++) {
  83         if (strcmp_P(name, traced_variables[i].name) == 0) {
  84             traced_variables[i].name = 0;
  85             traced_variables[i].addr = NULL;
  86             break;
  87         }
  88     }
  89 }
  90
  91 void verify_traced_variables(const char* func, int line) {
  92     for (int i = 0; i < NUM_TRACED_VARIABLES; i++) {
  93         traced_variable_t* t = &traced_variables[i];
  94         if (t->addr != NULL && t->name != NULL) {
  95             if (memcmp(t->last_value, t->addr, t->size) != 0) {
  96 #if defined(__AVR__)
  97                 xprintf("Traced variable \"%S\" has been modified\n", t->name);
  98                 xprintf("Between %S:%d\n", t->func, t->line);
  99                 xprintf("And %S:%d\n", func, line);
 100
 101 #else
 102                 xprintf("Traced variable \"%s\" has been modified\n", t->name);
 103                 xprintf("Between %s:%d\n", t->func, t->line);
 104                 xprintf("And %s:%d\n", func, line);
 105 #endif
 106                 xprintf("Previous value ");
 107                 for (int j = 0; j < t->size; j++) {
 108                     print_hex8(t->last_value[j]);
 109                 }
 110                 xprintf("\nNew value ");
 111                 uint8_t* addr = (uint8_t*)(t->addr);
 112                 for (int j = 0; j < t->size; j++) {
 113                     print_hex8(addr[j]);
 114                 }
 115                 xprintf("\n");
 116                 memcpy(t->last_value, addr, t->size);
 117             }
 118         }
 119
 120         t->func = func;
 121         t->line = line;
 122     }
 123 }